Arc extinction performance of SF6gas blast interrupter

With a model SF
6
gas blast interrupter, arc extinction performance was investigated. The measurements were carried out for di/dt values ranging from 13 ∼ 27 A/µs, for RRRV extending from 3.5∼ 13.0kV/µs and for a fixed pressure of 15kg/cm
²
. On the other hand, the voltage and current wave forms near current zero in the short line fault (SLF) test circuit were calculated employing Mayr's equation and the interrupting capability was investigated using the arc time constant and arc voltage obtained from the experimental results. From this calculation, the following relation was found. RRRVc ∞ (i)-
^(2.2∼2.45)
. The theoretical calculation was found to coincide satisfactorily with the experiments.